};
    }
  }

  @Override
  protected Map<String, String> makeEmptyMap() {
    Map<String, Integer> underlying = Maps.newHashMap();
    return transformValues(
        new UnmodifiableIteratorMap<String, Integer>(underlying), Functions.toStringFunction());
  }

  @Override
  protected Map<String, String> makePopulatedMap() {
    Map<String, Integer> underlying = Maps.newHashMap();
    underlying.put("a", 1);

		name     string
		metadata map[string]string
		keys     []string
		want     map[string]string
	}{
		{
			name:     "1",
			metadata: map[string]string{"content-type": "application/octet-stream", "etag": "de75a98baf2c6aef435b57dd0fc33c86", "x-amz-storage-class": "STANDARD", "md5": "abcde"},
			keys:     []string{"etag", "md5"},
			want:     map[string]string{"content-type": "application/octet-stream", "x-amz-storage-class": "STANDARD"},

    public static class ApiSystemInfoResponse extends ApiResponse {
        protected List<Map<String, String>> envProps;
        protected List<Map<String, String>> systemProps;
        protected List<Map<String, String>> fessProps;
        protected List<Map<String, String>> bugReportProps;

        public ApiSystemInfoResponse envProps(final List<Map<String, String>> envProps) {
            this.envProps = envProps;
            return this;

    EntryTransformer<String, Integer, String> transformer =
        new EntryTransformer<String, Integer, String>() {
          @Override
          public String transformEntry(String key, Integer value) {
            return key + value;
          }
        };
    ListMultimap<String, String> transformed = Multimaps.transformEntries(multimap, transformer);

        }

        @Override
        public String getDisplayName() {
            return String.format("%s{}", name);
        }
    }

    private static class PropertyLinkMetaData extends MethodLinkMetaData {
        private final String propertyName;

        private PropertyLinkMetaData(String propertyName, String methodName, String signature) {

   */
  static String nullToEmpty(@CheckForNull String string) {
    return (string == null) ? "" : string;
  }

  /**
   * Returns the string if it is not empty, or a null string otherwise.
   *
   * @param string the string to test and possibly return
   * @return {@code string} if it is not empty; {@code null} otherwise
   */
  @CheckForNull
  static String emptyToNull(@CheckForNull String string) {

    public void setId_Equal(String id) {
        setId_Term(id, null);
    }

    public void setId_Equal(String id, ConditionOptionCall<TermQueryBuilder> opLambda) {
        setId_Term(id, opLambda);
    }

    public void setId_Term(String id) {
        setId_Term(id, null);
    }

    public void setId_Term(String id, ConditionOptionCall<TermQueryBuilder> opLambda) {

    public static final String MAVEN_STYLE_ERROR_NAME = "error";
    public static final String MAVEN_STYLE_SUCCESS_NAME = "success";
    public static final String MAVEN_STYLE_FAILURE_NAME = "failure";
    public static final String MAVEN_STYLE_STRONG_NAME = "strong";
    public static final String MAVEN_STYLE_MOJO_NAME = "mojo";
    public static final String MAVEN_STYLE_PROJECT_NAME = "project";

    protected static final String LOCATION_HEADER = "Location";

    @Resource
    protected CrawlerContainer crawlerContainer;

    protected Map<String, String> featureMap = new HashMap<>();

    protected Map<String, String> propertyMap = new HashMap<>();

    protected Map<String, String> childUrlRuleMap = new LinkedHashMap<>();

    protected String defaultEncoding;

            String fieldName,
            ModelProblemCollector problems,
            Severity severity,
            Version version,
            String string,
            String sourceHint,
            InputLocationTracker tracker) {
        if (string == null || string.isEmpty()) {
            return true;
        }

        if ("true".equalsIgnoreCase(string) || "false".equalsIgnoreCase(string)) {